Subaqueous rock-breaker.



H. OOETEY. SUBAQUEOUS BOOK BREAKER. APPLICATION FILED AUG. 22,1908.

Patented Apr. 20, 1909.

Z-SHBBTS-SHEET 1.

2 BHEET8-SHEBT 2.

B.'H. GOFPBY. 'SUBAQUEOUS ROCK BREAKER.

APPLIGATION FILED AUG. 22, 1908.

Patented Apr. 20, 1909.

.. ac e the rock.

BARTON H. corrnr, or BoSToN, MASSACHUSETTS.

SUBAQUE QUS. ROCK-BREAKER.

Specification of Letters Patent.

Patented April 20, 1909.

Application filed August 22, 1908. Serial No. 449,801.

To all whom it may concern! Be it known that I, BARTON H. CQFFEY, a

citizen of the United States, residing at Boston, in the countyofSulfolk and State of Massachusetts, have invented a new and usefulImprovement Subaqueous Rock- Breakers, of which the following isaspecification.

The object of my invention is to provide an improved form ofrock-breakerbased on the principles of my broad patent Of September 11, 1900, No.657515; reissued June 26th 1906, No. 12501, wherein a caisson or tubefrom which the water is excluded, surrounds the rock-breaking machinery,thus eliminating all water resistances. In the first form practicallyused, a heavily weighted chiselwas elevated and dropped through the tubeupon the reef; and where the chisel landed on sloping surfaces of rock,violent side impacts were delivered to the steel walls of the tubetending to crystallizeand disrupt them. Also in certain varieties ofrock a fine sand is formed in the breaking process, which. entered thetube, clogged the action of the chisel and detracted from the efiiciencyof the apparatus. To avoid these defects I place a guide on the lowerend of the tube or caisson, so held that its axis always remains in Aline with the axis of the tube, and provided with openings for theescape of compressed air, the guide in turn supporting a chisel, whoseaxis coincides with its own. A heavy weight or hammer in the tube,iselevated and dropped upon the chisel, driving it into It is obviousthat no matter what character of surface thepoint of the chisel restsupon, the hammer blow must be transmitted in a straight line through theaxes of the connected parts, resulting in the elimination of all sideimpacts.

The form of caisson employed inv the apparatus described and claimed inthis Specification, is known as the pneumatic type, and may be definedas a partially submerged structure, embodying an air and water tightvessel to which com ressed air is supplied, and from which it isdischarged, through appropriate openings; the air pressure thusnecessarily maintained, keeping all spaces within the vessel above thelevel of the discharge openings, free from water. See CenturyDict.Caisson1; 'Ency. Brit.,9th edition, Caisson. PattonsflivilEngineering, Ed. 1895, paragraph 430, et seq. Y I am aware of a proposalto operate a.

chisel through a water tight joint at the lower end of a tube, thusforming a closed vessel, which is not a pneumatic caisson. In practicalwork, such provisions are unnecessary, very little sand is-formed, and astrong issuing current of air effectually prevents the entry of anysand,mud, etc. through contracted openings at the lower end of a pneumaticcaisson, and as the air pressure within the caisson must equal thehydrostatic pressure without, before air escapes, water is automatically excluded.

This construction eliminates the necessity of-maintaining tight jointsand accurate fits, which is obviously a difiicult problem, when theenormous Vibratory strains and shocks the parts are subject to, from therepeated blows of falling weights of from ten to twenty tons, areconsidered.

Another advantage is, that the air pressure Within the caisson can neverexceed the hydrostatic pressure outside, any increase in the volume ofair entering, simply causing an increased outflow through the openingsin the lower end of the caisson and guide, without any rise of pressure.I am thus enabled to employ the large volumes of air I find advantageousfor other purposes, described later on. In my preferred constructionFigures 1, 2 and 3 it is clear that a rise of pressure would cause anincreased upward reaction upon the caisson, tending to lift it from theguide, and thus destroy'the proper action of the apparatus. In actualoperation the depth of immersion is constantly changing, due to varyingdepths of bottom, rise and fall of tide, hoisting the caisson, etc. etc.In my apparatus the air pressure obviously automatically adjusts itselfto these varying conditions, whereas in a closed vessel, somecomplicated device would be necessary to eifect the same end.

Another advantage consists in the power of the issuing air currents tocreate water currents in the vicinity of the chisel, and sweep away mud,sand and other material, almost invariably found overlying ledges andreefs. For this purpose I use volumes of air largely in excess of thatnecessary to keep the caisson clear of water.

I Another advantage over the closed vessel,

lies in the complete absence of any Water whatever in the caisson solong as the air is escaping from thelower end, which is obviouslyconducive to high efficiency; and this desirable condition is constantlyvisible to the operating force by means of the air 1 The upper chamberis open to the atmosbubbles rising to the surface oi the water. 1 phere,the lower chamber 18 kept lree from In the closed vessel considerablewater might enter through leaky joints before detection.

The entry of broken rock through the openings in the guide is obviouslyimpossible, as the openings are above the level of such rock, at theextreme penetrations permissible with a given length of chisel, as shownat Fig. 3.

The maintenance of an air pressure within the caisson insures that anyleakage whatever will take place from within out, the tendency thereforebeing to prevent the entry of gritty substances between the movablesurfaces; a point of great practical importance with reference to wearand tear.

Another advantage of openings at the lower end of the caisson consists,in their forming an outlet for the escape of water that has entered thecaisson while standing idle without air pressure; as night, Sundays andholidays. In the closed vessel any water must be pumped out, or thewhole apparatus raised above the water level and drained; whereas in myapparatus, the air pressure quickly forces the water through theopenings until the caisson is free. Thus the same agency that keepswater from entering the caisson, also empties it.

Reference now being had to the drawingsz Fig. 1. is an end view of thehull or float supporting the rock-breaking apparatus, floating at thewater line W- W and showing the caisson in the working position markedY., and the moving position in dotted lines marked Y Fig. 2. is anelevation of Fig. 1. showing the hull and caisson in section on thecenter line of Fig. 1. Fig. 3. is an enlarged view of the chisel mypreferred form of guide and the lower end of the caisson; representingthe conditions existing where the chisel has been driven to its extremepenetration. Fig. l. is an alternate form of construction shown also insection.

In detail 1, is the caisson, a vertical cylinder closed to theatmosphere and open at the lower end preferably of steel; supported bythe guide 2, which embraces its lower end with an easy fit, permittingvertical and retary movement between the two. The guide 2, rests uponthe chisel 3, with provision for relative vertical movement. The chisel3, stands upon the reef and supports all the parts in the workingposition Y, Fig. 1.

The assemblage is prevented from falling over by the pins 4, integralwith the caisson, which are inserted in the guide shoes 5, which in turnslide freely on the vertical guides 6, secured to the frame 7, in turnsupported by the float 8, and over the well 9. The float 8 is heldagainst horizontal movement by anchors or spuds (not shown).

The caisson is divided into two chambers, by the diaphragm 10 integralwith its walls.

water and full of compressed. air, by means of the air compressor 1;,the pipes 13 and 14, and flexible hose 15, the compressed air escapingat the openings 16 in the guide 2. Other than air ca be used for thesame purpose.

In the lower chamber of the caisson and free to reciprocate\-'ertically, is the weight or hammer 17, loosely fitting the *alls ofthe caisson at the rings .18, and provided with passages 19 for themovement of air, during its elevation and fall. The hammer is lifted bythe rod 20, passing into the upper chamber of the caisson through thestulling boy. 1 1, and terminating in the barbed end 21. Upon fallingthe hammer strikes the cap22 of the chisel 3, which transmits its energyto the reef below.

The lifting apparatus consists of a boiler, engine and auxiliaries notshown and contained in that portion of the hull 8, broken away. Theengine turns the drum 23, bus operating the cable 25, which passes overthe sheave 26 and lifts or lowers the bellmouthed clutch 27, fitted withthe trip .lo'vvr 2S, and trip chain 29, which in turn is threaded aroundthe sheaves 30, to bring the free end to the out-side of the caisson forconvenient operation.

When it becomes mcessary to hoist the caisson, the guide 2, is preventedfrom dropping oli', by the side chains 31, connecting the two, clearlyshown; the cap 22 serving to support the chisel 3, under the samecircumstances.

In the alternate construction Fig. 4. a guide 32 integral with thecaisson 1, is omployed; with openings 33, for the. escape of compressedair. In other respects th apparatus is similar to that alreadydescribed.

The operation of the machine is as follews:rrfter the lloat S is mooredover the reef, either by anchors or spuds (not shown) the caisson islowered until the chisel 3, rests upon the rock. in this position itwill be observed the entire weight of the connected parts is upon therock. The clutch 27 is then lowered over the barbed end 21 of the rod20, engaging same; the clutch is then hoisted raising the hammer 17, toany desired point within the limit of the machine (as the position K,Fig. 2, shown in dotted lines) when a pull on the trip chain 29,releases the clutch and permits the hammer to fall and strike the cap22, forcing the chisel 3, into the rock. When sufiicient depth is soobtained at any desired point, the hammer is clutched and raised untilit engages the lower side of the diaphragm 10, on further hoisting, thecaisson, guide and chisel lift also, sliding vertically in the guides 6,until the position of Y Fig. 1. is assumed; the chisel 3, being thenclear of the ledge, the float 8, can be moved to a fresh position, thechisel again loweredto the rock, and breaking operations resumed. b

As in my former patent referred to, the leading feature of thisinvention consists in providing a caisson or cylinder means forv keepingit free from water when submerged, so that the rock-breaking machinerycan work unhampered by the water resistance.

As the details of this machine can be variedcifically protected by otherpatents.

Having described my invention I claim 1. In a subaqueous rock-breaker,the combination of a pneumatic caisson normally open at the lower end,and a chisel movably guided at the lower caisson end, the constructionand arrangement of parts being such as not to obstruct free andcontinuous air escape at the lower caisson end, ahammer adapted toreciprocate within the caisson and strike the chisel but not attached tosame, means to reciprocate the hammer and means for forcing compressedair into the caisson to exclude water, sand, mud, etc. for the purposesset forth.

2. In a subaqueous rock-breaker, the combination of an upright tubularmember, a hammer movable therein and substantially occupying the entirecross section of said tubular member, said hammer constructed with airpassages connecting the air spaces below and above said hammer, and achisel movably fitted at the lower end of said tubular member.

3. In a subaqueous rock-breaker, the combination of a pneumatic caissonnormally open at the lower end, and 'a chisel movably guided at thelower caisson end, the construction and arrangement of parts being suchas not to obstruct free and continuous air escape at the lower caissonend, a hammer adapted to reciprocate within the caisson and strike thechisel but not attached to same, means to reciprocate the hammer andmeans for forcing compressed air into the caisson to exclude water,sand, mud, etc., in combination with a guide frame mounted on a float,adapted to hold the caisson upright while permitting vertical movementof same; and means for lifting and lowering the caisson for the purposesset forth.

4. In a subaqueous roclobreaker, the combination of a pneumatic caissonnormally open at the lower end, and a chisel movably guided at the lowercaisson end, the construction and arrangement of parts being such as notto obstruct free and continuous air escape at the lower caisson end, incombination with means for forcing compressed air into the caissoninexcess of that necessary to exclude water, sand, mud, etc. for thepurposes set forth.

5. In a subaqueous rock-breaker, the combination of a pneumatic caisson,a chisel movably guided at the lower caisson end, means for forcingcompressed air into the caisson; and openings for the escape ofcompressed air placed above the level of broken rock, for the purposesset forth.

6. In a subaqueous rock-breaker, a pneumatic caisson divided into twocompartments by a diaphragm, openings from the upper compartment to theatmosphere, and openings from the lower compartment for ,the escape ofcompressed air; in combination with a chisel movably guided at the lowercaisson end, and means for forcing compressed air into the lowercompartment, for the purposes set forth.

7. In a subaqueous rock-breaker, the combination" of a pneumatic caissonwith its lower end fitted as a guide, a chisel movable upon said guide,a hammer reciprocating in said caisson and means for forcing compressedair into the caisson for the purposes set forth.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

BARTON H. COFFEY.

Witnesses:

J. T. B. CoFFEY, ELEANOR V. TUFTS.

